In 363, on this day Emperor Julian defeated Sharpur II. After a divine vision foretold Constantine's victory over Maxentius at Milvian Bridge in 312, he determined to reverse the persecution of Christians in the Roman Empire. In 313, Constantine issued the Edict of Milan, returning confiscated property to churches and affirming freedom of religion granted by Galerius in 311. His mother, Helena, led expeditions to sites important to Christianity such as the birthplace of Christ in Bethlehem, and Constantine used his resources to build cathedrals after cathedral upon them, such as the Church of the Nativity.

Emperor Julian defeated Sharpur IIIn 325, Constantine commanded bickering bishops to meet at the Council of Nicaea, which clarified doctrine, hamstrung Arianism, and made Christianity far more political.

After Constantine's death, his three sons inherited the empire, which soon fell into civil war again. Constantius II, the second son, eventually gained control and reorganized his command structure with those who had proven loyal. Among them was his bookish cousin Julian, who had spent much of his life in exile at studies of philosophy and religion. Julian had become a lector in the Church, but Constantius ordered him to become the representative Caesar in Gaul to keep further rebellions from arising. There, Julian learned the art of war while defeating Franks and Germans and winning utter loyalty of his soldiers. He also abandoned Christianity, instead seeing religion in the Neoplatonic perspective as metaphor for ideals, a metaphor better viewed, he believed, through pagan myth and ritual.

A new article by Jeff ProvineRenewed war with the Sassanids in Persia prompted Constantius to recall half of Julian's forces in 360. Julian, who had become even more popular by seizing civilian rule and preventing tax increases toward corrupt local government, refused. His soldiers dubbed him "Augustus", and Julian marched to war against his cousin in 361. Constantius fell deathly ill and, to stave off civil war, pronounced Julian the rightful ruler of Rome. Julian arrived in Constantinople and began abolishing the autocratic practices established by Constantine, whom he blamed for corruption throughout the empire. He also blamed the weakness of Roman values, which he attributed to the spread of Christianity. While encouraging his peers to take up pagan ritual again, Julian stripped the Church of privileges and required that all public educators had to be approved by him, ending the careers of numerous Christian tutors. To spread his popularity and speed the demise of Christianity, which had become integral as the empire's system of charity, he began to create state philanthropy and universal ethical codes for priests regardless of religion.

While Julian worked to push his reforms through, issues arose in the East as the Sassanids continued their harassment of Roman fortifications and its ally, Armenia. He settled in Antioch (known for its wealth of temples to Apollo) for a time and solved a food shortage by forcing land-holders to sell. From there, he built up a massive expeditionary force of nearly 100,000 and marched into Persia. His armies moved enigmatically, feigning invasions northeastward to draw out King Shapur II and his army, while Julian's main force worked its way down the Euphrates to attack the Sassanian capital at Ctesiphon across the Tigris. The defenders determined to attack him in the field, but Julian won a staggering victory where 2,500 Sassanids died versus seventy Romans. Julian met with his commanders to determine action as the Romans did not have the equipment for a siege and Shapur's larger army was returning quickly while 30,000 Romans who had been a distraction in the north. The general consensus was a retreat to regroup, but Julian refused and dubbed himself the avatar of Alexander the Great.

Julian ordered a siege of Ctesiphon, which proved to be yet another feint. When Shapur arrived, he withdrew the sieging troops to the marshlands that had been flooded by locals breaking dykes as defense against Julian's arrival. Shapur attacked, but the wet ground made his heavy cavalry and war elephants useless. The light Romans, however, held high ground and were able to defeat the soldiers sent against them. When Shapur's army began to retreat, Julian signaled the counterattack, which drove the Sassanids to flee. Shapur was captured, and Julian became the conqueror of Persia.

Julian stayed in Persia for years to maintain control and began adapting to the eastern cultures. His religious philosophy proved to welcome new cults such as Mithras and Isis, which he exported all over Rome. Money from the conquests went to projects to support other religions, such as Judaism, for whom Julian rebuilt the Temple in Jerusalem despite fires caused by an earthquake in Galilee that had driven away workers during the first attempt in 363. Christianity dwindled into one of a multitude of religions, all represented in Rome, whose Pantheon served as the capitol of all belief toward the platonic ideal. Political rule, which governed and promoted religious action, was maintained in Constantinople.

The Persian frontier proved difficult to hold as Huns attacked, but it served well as a buffer for Rome. Germans were welcomed into the empire fluidly due to Julian's universalist appeals, as were the later Huns upon their settlement of eastern Europe. Eventually the Roman Empire fell due to myriad reasons, particularly civil war as particular cults rose up against corrupt leaders. The tradition of religious egalitarianism continues with periodic new cults coming to the forefront while others faded. Christianity continues as a general belief held by many largely as a social philosophy of "love thy neighbor" and held stringently only by a few ascetic monks.